Use UIScrollView delegate methods instead of KVO

I'm using a custom view that conforms to SSPullToRefreshContentView, if that makes a difference. But when I drag downward until the state is SSPullToRefreshViewStateReady, and release the touch from a static velocity (i.e. don't "fling" the scrollview downward) the content view seems to instantly shift upward by about 20px before smoothly transitioning to the correct content inset. For me, using UIScrollView delegate methods instead of KVO solves the problem. Might be something to look into.